I do not think the PRC is "neck and neck" with the US on a X-47B-like UCAV at all. Look at the last ten years with the Predators, Reapers, Global Hawk, and so many others. All of these are battle/combat proven and have been operational for years. That's a lot of accumulated knowledge in design and operations and all of the components that go into that.
I believe the PRC has designed and built a prototype that looks a lot like the X-47B...but even then, the finer characteristics just are not there...which means that the engines, avionics, controls, etc. are probably also equally lacking when compared.
No, I believe the US will have an operational, stealthy, and very capable recon/surveil/patrol/stike UCAV operating off of their carriers in the 2020 time frame.
If the PLAN does this at all wiith anything as sophistiaceted, I expect it is going to be five years later at the least, and probably more like 7-8 years. And that is if they do it at all, that is, having anything equal to the X-47B launching from and landing on carriers for the PLAN.
There is no dounbt they will launch other, much less sophisticated UAVs off of their vessels, but the US has been doing that for almost 20 years.
So, no "knock" against the PRC or the PLAN. They are doing amazing things...and many of them faster than most analysts thought. In this area, they simply do not have the components together to make it work at this point. Heck, they haven't cat alunched any type of aircraft off of a carrier yet. They will not be able to match the performance and weight, and combat radius of this UCAV with the load it can carry until they do...and that itself is several years away.